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<h2><span class="refentrytitle">Macro BOOST_PROTO_AUTO</span></h2>
<p>BOOST_PROTO_AUTO — For defining a local variable that stores a Proto expression template,
      deep-copying the expression so there are no dangling references.</p>
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<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2>
<div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: &lt;<a class="link" href="proto/reference.html#header.boost.proto.proto_typeof_hpp" title="Header &lt;boost/proto/proto_typeof.hpp&gt;">boost/proto/proto_typeof.hpp</a>&gt;

</span>BOOST_PROTO_AUTO(Var, Expr)</pre></div>
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<a name="id-1.3.34.5.38.4.4"></a><h2>Description</h2>
<p>
        To define a local variable <code class="computeroutput">ex</code> that stores the expression
        <code class="computeroutput"><a class="link" href="boost/proto/lit.html" title="Function lit">proto::lit</a>(1) + 2</code>,
        do the following:</p>
<pre class="programlisting"><span class="identifier">BOOST_PROTO_AUTO</span><span class="special">(</span> <span class="identifier">ex</span><span class="special">,</span> <a class="link" href="boost/proto/lit.html" title="Function lit">proto::lit</a><span class="special">(</span><span class="number">1</span><span class="special">)</span> <span class="special">+</span> <span class="number">2</span> <span class="special">)</span><span class="special">;</span></pre>
<p>.
        The above is equivalent to the following:
        </p>
<pre class="programlisting"><span class="identifier">BOOST_AUTO</span><span class="special">(</span> <span class="identifier">ex</span><span class="special">,</span> <a class="link" href="boost/proto/deep_copy.html" title="Function template deep_copy">proto::deep_copy</a><span class="special">(</span> <a class="link" href="boost/proto/lit.html" title="Function lit">proto::lit</a><span class="special">(</span><span class="number">1</span><span class="special">)</span> <span class="special">+</span> <span class="number">2</span> <span class="special">)</span> <span class="special">)</span><span class="special">;</span></pre>
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<td align="right"><div class="copyright-footer">Copyright © 2008 Eric Niebler<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
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